CourseRoleDB.ts

import {CourseRole} from "../../../models/enums/CourseRoleEnum";
import {convertRolePermission} from "../../../models/database/RolePermission";
import {removeItem, addItem} from "../../../helpers/EnumHelper";

import {pool, extract, map, one, toBin, pgDB} from "./HelperDB";

/**
 * Interface for interacting with role permissions
 * @Author Rens Leendertz
 */
export class CourseRoleDB {
    /**
     * get all roles currently stored in the database, given to onSuccess as a list of Permission
     */
    static async getAllRoles(DB: pgDB = pool) {
        return DB.query("SELECT * FROM \"CourseRolePermissions\"")
            .then(extract).then(map(convertRolePermission));
    }

    /**
     * get all permissions associated with a role currently stored in the database by name,
     * given to onSuccess as an Permission
     */
    static async getRolePermissions(role: string, DB: pgDB = pool) {
        return DB.query(`SELECT *
            FROM "CourseRolePermissions"
            WHERE courseRoleID=$1`, [role])
            .then(extract).then(map(convertRolePermission)).then(one);
    }

    /**
     * Add a new role to the database
     */
    static async addNewCourseRole(name: string, permissions: number, DB: pgDB = pool) {

        //this might not be the best place,
        // this will add an entry to the courseRole enum.
        addItem(CourseRole, name);

        return DB.query(`INSERT INTO "CourseRolePermissions"
            VALUES ($1,$2)
            RETURNING *`, [name, toBin(permissions)])
            .then(extract).then(map(convertRolePermission)).then(one);
    }

    /**
     * set the the permissions for a role in the database.
     * all old permissions will NOT be retained.
     */
    static async setPermissionOnRole(name: string, permissions: number, DB: pgDB = pool) {
        return DB.query(`UPDATE "CourseRolePermissions"
            SET permission = $2
            WHERE courseRoleID=$1
            RETURNING *`, [name, toBin(permissions)])
            .then(extract).then(map(convertRolePermission)).then(one);
    }

    /**
     * Add some permissions to a role in the database
     * the @param permission should be constructed using the localPermissions Enum inside enums/CourseRoleEnum
     * If the role already has some of the rights, those will be retained
     * No permissions will be removed
     */
    static async addPermissionToRole(name: string, permission: number, DB: pgDB = pool) {
        return DB.query(`UPDATE "CourseRolePermissions"
            SET permission=permission | $2
            WHERE courseRoleID=$1
            RETURNING *`, [name, toBin(permission)])
            .then(extract).then(map(convertRolePermission)).then(one);
    }

    /**
     * Remove some permissions from a role in the database
     * the @param permission should be constructed using the localPermissions Enum inside enums/CourseRoleEnum
     * If the role already does not have (some of) the rights, those will not enabled
     * No permissions will be added
     */
    static async removePermissionFromRole(name: string, permission: number, DB: pgDB = pool) {
        return DB.query(`UPDATE "CourseRolePermissions"
            SET permission=permission & (~($2::bit(40)))
            WHERE courseRoleID=$1
            RETURNING *`, [name, toBin(permission)])
            .then(extract).then(map(convertRolePermission)).then(one);
    }

    /**
     * Remove a role from the database.
     * This may fail due to foreign key constraints if there are still users with this role in a course.
     * make sure to change those permissions first.
     */
    static async deleteCourseRole(name: string, DB: pgDB = pool) {
        return DB.query(`DELETE FROM "CourseRolePermissions"
            WHERE courseRoleID=$1
            RETURNING *`, [name])
            .then(extract).then(map(convertRolePermission)).then(one).then(res => {
                //this will also remove the entry from the courseRole enum on the server,
                //no longer allowing it as a valid item.
                removeItem(CourseRole, name);
                return res;
            });
    }
}